DE102019202753B3 - Body structure for an electrically powered vehicle - Google Patents

Abstract

The invention relates to a body structure for an electrically operated vehicle, with an assembly space (12) for a traction battery (9) which is open in the vehicle vertical direction (z) towards the vehicle and which is bounded by a vehicle floor panel part (10) to the top of the vehicle, the traction battery (9 ) is inserted from below into the assembly space (12), and a housing flange (19) of the traction battery (9) engages under a sheet metal profile part (10) on the body side and is screwed from below to the sheet metal profile part (10) at at least one screw point (21), wherein the screwing point (21) has a screw bolt (25) aligned in the vehicle vertical direction (z), which is guided with clearance through a housing flange lead-through channel (27) and through a sheet metal profile screw hole, and is screwed onto a weld nut (31) the side of the sheet metal profile part (22) facing away from the housing flange (19) is welded on, so that the housing flange (19) is clamped between a screw head (33) of the screw bolt (25) and the sheet metal profile part (10), and in the event of a crash the traction battery (9) is displaced due to a crash until an inner wall of the housing flange duct (27) removes the screw bolt (25 ) presses against an opening edge (51) of the sheet-metal part screw hole, specifically under the shear load of the screw bolt (25). According to the invention, in order to reduce the shear stress, the welding nut (31) is extended with a shank (35) which at least protrudes into the sheet metal part screw hole. In the event of a crash, the screw bolt (25) presses against the opening edge (51) of the sheet metal part screw hole with the welding nut shaft (35) in between.

Description

The invention relates to a body structure for an electrically operated vehicle according to the preamble of claim 1.

An electrically operated vehicle can have an open mounting space for a traction battery in the vehicle vertical direction, which is bounded by a vehicle floor panel part according to the vehicle. In this case, the traction battery can be inserted into the assembly space from below and screwed to the body structure. The traction battery mounting space can be limited in the vehicle longitudinal direction by front and rear cross members of the body structure and in the vehicle transverse direction by lateral sills of the vehicle. In the event of a crash (from the side, in the longitudinal direction or off-center, that is to say offset crash), the traction battery can thus act as a push field by means of which the crash energy is passed on from a vehicle side facing the crash to a vehicle side facing away from the crash.

In a generic body structure, a housing flange of the traction battery engages under a body-side sheet metal profile part of a side sill or a cross member of the body structure. The housing flange of the traction battery is screwed from the vehicle below to the sheet metal profile part at at least one screw point. The screwing point has a screw bolt oriented in the vertical direction of the vehicle, which is guided with clearance through a housing flange lead-through channel and through a sheet metal part screw hole and is screwed with a weld nut. The weld nut is welded onto the side of the sheet metal profile part facing away from the housing flange. In the assembled position, the traction battery housing flange is therefore clamped between a screw head of the screw bolt and the sheet metal profile part.

In the event of a crash, the traction battery is moved (transversely to the screwing direction) as a result of crashes until an inner wall of the housing flange bushing strikes against the screw bolt using the play of holes and the screw bolt presses against an opening edge of the sheet metal part screw hole, namely under shear stress on the screw bolt.

The sheet metal profile part is usually realized as a high-strength hot-formed part, so that its trimmed edge acts like a knife on the screw bolt in the above crash. There is therefore a risk that the bolt will be sheared off due to the shear stress acting on it.

From the generic DE 10 2011 102 412 A1 an arrangement of a traction battery in a vehicle is known. From the DE 93 20 666 U1 a connecting element for use in resistance pulse welding according to the capacitor discharge principle is known.

Out DE 199 01 299 C1 a connection of a stabilizer to a carrier by means of a bracket is known, which is arranged in the immediate vicinity of the connecting bolt between the carrier, in particular the subframe, and a vehicle body.

Out DE 10 2015 016 492 A1 is known a body structure for a two-lane vehicle, with a subframe for a vehicle rear axle in particular. The subframe is connected to the vehicle body via a screw connection point. The body structure has at least one protective element on the side of the screw connection point facing the rear crash, which is connected to the vehicle body via the screw connection point. In the event of a rear-end crash, the protective element can be deformable with the breakdown of crash energy. Alternatively or additionally, in the event of a rear-end crash, the protective element and the screw connection point can be connected in a load path, via which the impact forces introduced can be transmitted from the protective element into the vehicle body.

Out DE 10 2018 100 152 A1 an electric vehicle is known which contains a chassis and a battery pack, which are arranged at the bottom and inserted into the chassis. The chassis includes a first cross member and the battery pack includes a support structure with a first cross-sectional component. The first cross-sectional component extends together and is inserted with that on the first cross member.

Out US 2016/0 207 569 A1 an upper plate portion of a suspension member and a bottom plate portion of a bracket disposed on an upper surface thereof are known. Likewise, as objects to be fastened, they are arranged between a weld nut and an end face on a vehicle upper side of a collar. A protruding portion protruding toward a bolt through hole side of the bottom plate portion of the bracket is formed at an end portion on the vehicle top of the collar. The protruding portion is formed along an entire circumference around an axis of the collar. In addition, a drainage groove is formed in the collar, which leads from the end surface on the vehicle top to an outer peripheral surface of the collar.

The object of the invention is to provide a body structure for an electrically operated vehicle, in which a crash-proof connection of the traction battery to the body structure is made possible in a simple manner.

The object is solved by the features of claim 1. Preferred developments of the invention are disclosed in the subclaims.

According to the characteristic part, the weld nut is extended with a shank to reduce the shear stress caused by the crash. The weld nut shaft protrudes at least into the sheet metal part screw hole. In the event of a crash, the screw bolt is no longer pressed directly against the opening edge (i.e. the trimmed edge) of the sheet-metal part screw hole, but rather with the welding nut shaft being interposed. By providing the welding nut shank, it is no longer just the bolt core diameter that is the “partner” of the shear stress. Rather, the effective bolt diameter, which counteracts this shear stress, is increased by using the weld nut shaft.

In a technical implementation, the welding nut shaft can protrude with a protrusion from the side of the sheet metal profile part facing the housing flange. Therefore, the weld nut shaft extends into the housing flange lead-through channel. In the event of a crash, the inner wall of the housing flange through duct no longer presses directly against the screw bolt, but rather with the welding nut shaft interposed.

In the assembled position, the screw head of the screw bolt is braced against an opening edge area of the housing flange duct. In order to ensure a perfect screw connection, the weld nut shaft with its shaft end face facing the screw head of the screw bolt can be spaced apart from the screw head of the screw bolt by an axial clearance.

It is preferred if the inner wall of the housing shaft feedthrough channel does not completely have a constant inside diameter over the channel length, but rather is divided into a large-diameter channel section and a small-diameter channel section which merge into one another at an annular shoulder. In this case, the small-diameter channel section on the side facing the screw head can preferably merge into the end opening area of the housing flange through-channel, against which the screw head of the screw bolt is braced. The small-diameter duct section ensures a sufficiently large support surface between the screw head and the front edge area of the housing flange duct. The large-diameter duct section, on the other hand, ensures a free radial gap between the weld nut shaft and the inner wall of the housing flange duct.

According to the invention, both the inner wall of the housing flange lead-through channel and the shank nut shaft are designed with stop contours in order to ensure a perfect transfer of force from the traction battery into the body-side sheet-metal profile part in the event of a crash, with largely force-free bridging of the screw bolt in order to cause a screw bolt material failure avoid.

Against this background, the axial length of the small-diameter channel section can be made smaller than the axial clearance between the end face of the weld nut shaft and the screw head of the screw bolt. The small-diameter channel section and the axial clearance can preferably be arranged in radial alignment with one another.

In this case, there is a preferred crash course described below: For example, the large-diameter channel section of the housing flange lead-through channel can come into contact with the outer circumference of the weld nut shaft transversely to the screwing direction, while the small-diameter channel section can get into the axial clearance (between the shaft end face and the Screw head of the bolt).

In addition, the outer circumference of the weld nut shaft can merge into the end face of the shaft on a circumferential outer corner. Corresponding to this, a circumferential inner corner can be formed between the large-diameter channel section and an annular surface of the annular shoulder, which forms a negative shape of the outer shaft corner. In this case, in the event of a crash, the inner corner in the housing flange lead-through channel can engage around the outer shaft corner in a form-fitting manner.

To reduce the shear stress on the screw bolt, it is important that direct contact between the small-diameter duct section of the housing flange bushing duct and the bolt shank of the screw bolt is avoided. Against this background, the small-diameter channel section can protrude radially inward by a radial offset from the large-diameter radial section. The radial offset can be dimensioned smaller than a wall thickness of the Weld nut shaft. This ensures that in the event of a crash, the small-diameter duct section remains out of contact with the bolt shaft of the screw bolt.

In a further embodiment, the housing flange can be clamped against the sheet metal profile part with the interposition of a clamping sleeve, which is rotationally symmetrical. The clamping sleeve can be supported with a support base on the housing flange, which has a hollow cylindrical vehicle-lower sleeve section that merges at a transition edge into a radially outwardly projecting peripheral flange. The screw bolt is guided through the adapter sleeve. The hollow cylindrical sleeve section can be in contact with the inner wall of the large-diameter channel section of the housing flange bushing channel, while the transition edge and the radially outwardly projecting support flange are supported on the opening edge region of the housing flange bushing channel facing the sheet metal profile part. In addition, the clamping sleeve can be supported with a sleeve section on top of the vehicle at the opening edge area of the sheet-metal part screw hole.

An exemplary embodiment of the invention is described below with reference to the attached figures.

• 1 in einer perspektivischen Teilraumansicht eine Karosseriestruktur eines elektrisch betriebenen Fahrzeugs;
• 2 eine Teilschnittdarstellung entlang einer Schnittebene yz aus der 1;
• 3 eine vergrößerte Schnittdarstellung einer Schraubstelle aus der 2 bei normalem Fahrbetrieb; und
• 4 eine Ansicht entsprechend der 3 bei einem Seitencrashfall; sowie
• 5 und 6 jeweils Ansichten weiterer Ausführungsbeispiele.

Show it:

• 1 in a perspective partial space view a body structure of an electrically operated vehicle;
• 2nd a partial sectional view along a section plane yz from the 1 ;
• 3rd an enlarged sectional view of a screw from the 2nd in normal driving; and
• 4th a view corresponding to the 3rd in the event of a side crash; such as
• 5 and 6 views of further exemplary embodiments.

In the 1 shows the body structure of a two-lane vehicle, which is described below insofar as is necessary for an understanding of the invention. As a result, the body structure has two side sills that run in the vehicle longitudinal direction x 1 on, of which in the 1 only one is shown. The sill 1 extends in the vehicle longitudinal direction x between a front A-pillar 3rd and a rear C-pillar 5 and limits side door openings on the bottom 7 . There is a crash-sensitive traction battery in the vehicle floor of the body structure 9 installed. This is below a floor panel part 10th positioned and extending in the vehicle transverse direction y between the two sills 1 . The traction battery extends in the vehicle longitudinal direction x 9 between a front cross member and a rear cross member, which are not shown in the figures.

As from the 1 emerges is the traction battery 9 viewed in the vehicle vertical direction z at approximately the same height as the sills 1 positioned. The traction battery 9 points in the 2nd a battery case 13 with a housing side wall 16 , a top wall 15 as well as a bottom wall 17th . The housing side wall 16 is with a laterally projecting housing flange 19th trained the sill 1 reaches under and with a sheet profile part 22 of the sill 1 in a screw connection 21 is. In the 2nd is only half of the body structure down to the vehicle center level E shown. The other half, not shown, is designed to be approximately a mirror image of this. In the event of a side crash described later, the impact forces C ( 4th ) from the crash-facing sill 1 in a cross load path where the traction battery 9 is integrated as a rigid shear panel in the direction of the sill facing away from the crash 1 forwarded.

Based on 3rd is the screwing point below 21 described: Accordingly, the housing flange 19th from the vehicle bottom by means of a screw bolt aligned in the vehicle vertical direction z 25th screwed. The bolt 25th is with clearance through a housing flange duct 27 and passed through a sheet metal part screw hole and with a weld nut 31 screwed. The sweat nut 31 is in the 3rd on the, the housing flange 19th opposite side of the sheet metal profile part 22 welded on. Hence the housing flange 19th between a screw head 33 of the bolt 25th and the sheet metal part 22 tightened.

In the 3rd is the sweat nut 31 with a shaft 35 extended, which extends through the sheet metal part screw hole and with a protrusion a the the housing flange 19th facing side of the sheet metal part 22 towered over. The screw head 33 of the bolt 25th is in the 3rd against a front opening edge area 37 of the housing flange duct 27 tense. In addition, the weld nut shaft 35 in the 3rd with his, the screw head 33 of the bolt 25th facing end face 39 around an axial clearance Δz from the screw head 33 of the bolt 25th spaced.

As from the 3rd further emerges, has an inner wall of the housing flange bushing 27 a large one Canal section 43 and a small-diameter channel section 45 that merge into each other on a ring shoulder. The small-diameter channel section 45 goes on the screw head 33 facing side in the opening edge area 37 of the housing flange duct 19th over against which the screw head 33 of the bolt 25th is tense.

The axial length b ( 4th ) of the small-diameter duct section 45 is dimensioned smaller than the axial clearance Δz between the face of the shaft 39 and the screw head 33 of the bolt 25th . In addition, in the 3rd the small-diameter channel section 45 and the axial clearance Δz in radial alignment (ie. in the vehicle transverse direction y) to each other.

The following describes the course of the crash in the event of a side crash in which the traction battery 9 in a crash direction C ( 4th ) inside the assembly room 12th is shifted in the vehicle transverse direction y: Accordingly, the large-diameter channel section abuts 43 of the housing flange duct 27 against the outer circumference of the weld nut shaft 35 , during the small-diameter channel section 45 in the axial clearance Δz between the face of the shaft 39 and the screw head 33 drives in.

The small-diameter channel section 45 is in the 3rd about a radial offset Δr compared to the large-diameter channel section 43 offset radially inwards. The radial offset Δr is smaller than a wall thickness of the weld nut shaft 35 . This ensures that in the event of a crash ( 4th ) the small-diameter channel section 45 out of contact with the bolt shaft 49 of the bolt 25th remains. Using the above component geometry at the screw point 21 that results in the 4th indicated crash load path L , where the crash load from the battery case 13 over its housing flange 19th in the weld nut shaft 35 is introduced and from there via the opening edge (ie trimming edge) 51 into the sheet metal part 22 the body is forwarded. The bolt shaft 49 of the bolt 25th thus does not come with the bleed edge 51 of the sheet metal part 22 still with the inner wall of the housing flange duct 27 in direct contact, causing one on the bolt 25th acting shear load transverse to the screwing direction S is reduced.

Like from the 3rd and 4th the outer circumference of the weld nut shaft goes further 35 on an all-round outside corner 53 in the face of the shaft 39 over. The same is true in the 3rd between the large-diameter channel section 43 and an annular surface 55 a circumferential inside corner 57 stretched out, which is a negative form of the shaft outside corner 53 forms. In the event of a crash ( 4th ) encompasses the inside flange of the housing flange 57 the shaft outside corner 53 form-fitting.

In the 5 is in a view corresponding to that 3rd a screw point 21 shown according to a second embodiment, the geometry of which is essentially identical to the previous first embodiment. In contrast to 3rd or 4th is in the 5 the ring surface 55 the ring shoulder over a free axial distance d from the face of the shaft 49 spaced.

In the 6 is a screw connection 21 shown according to a further embodiment. Accordingly, in the 6 the housing flange 19th with the interposition of an adapter sleeve 59 against the sheet metal part 22 clamped, which is rotationally symmetrical. The adapter sleeve 59 is with a support base on the housing flange 19th supported. The support base consists of the 6 from a hollow cylindrical vehicle lower sleeve section 61 that is on a transition edge 63 in a radially outwardly projecting peripheral flange 65 transforms. Through the adapter sleeve 59 is the bolt 25th guided. The hollow cylindrical sleeve section 61 is in the 6 in contact with the large-diameter channel section 43 of the housing flange duct 27 while the transition edge 63 and the support flange projecting radially outwards 65 on the, the sheet metal part 22 facing opening edge area 67 of the housing flange duct 27 is supported. In addition, the adapter sleeve has 59 with a sleeve section above the vehicle 60 supported at the opening edge area of the sheet metal part screw hole.

The following describes the course of the crash in the event of a side crash in which the traction battery 9 in a crash direction C ( 6 ) inside the assembly room 12th is shifted in the vehicle transverse direction y: Accordingly, the sleeve section above the vehicle abuts 60 the adapter sleeve 59 to the outer circumference of the weld nut shaft 35 while vehicle lower sleeve section 61 the adapter sleeve 59 in the axial clearance Δz between the face of the shaft 39 and the screw head 33 retracts without the bolt shaft 49 of the bolt 25th to touch.

Reference list

1

Sill

3rd

A pillar

5

C pillar

7

Side door opening

9

Traction battery

10th

Floor panel part

12th

Assembly room

13

Battery case

16

Housing side wall

15

Top wall

17th

Bottom wall

19th

Housing flange

21

Screw connection

22

Sheet metal part

25th

Bolts

27

Housing flange duct

31

Welding nut

33

Screw head

35

Weld nut shaft

37

Opening edge area

39

Face of the shaft

43

large-diameter channel section

45

small-diameter duct section

49

Stud shank

51

Bleed edge

53

Outside corner

55

Ring surface

57

Inside corner

59

Adapter sleeve

60

upper sleeve section of the vehicle

61

lower sleeve section

63

Transition edge

65

Support flange

67

Opening edge area

E

Median longitudinal plane

S

Screw direction

L

Load path

a

Got over

b

Axial length

d

free axial distance

Δz

axial clearance

Δr

Radial offset

Claims (8)

Body structure for an electrically operated vehicle, with an assembly space (12) for a traction battery (9) which is open in the vehicle vertical direction (z) towards the vehicle bottom and which is delimited to the top by a vehicle floor panel part (10), the traction battery (9) from the vehicle bottom in the assembly space (12) is inserted, and a housing flange (19) of the traction battery (9) engages under a sheet metal profile part (10) on the body side and is screwed from below to the sheet metal profile part (10) at least one screw point (21), the screw point ( 21) has a screw bolt (25) aligned in the vertical direction of the vehicle (z), which is guided with clearance through a housing flange lead-through channel (27) and through a sheet metal profile screw hole, and is screwed to a weld nut (31) which is on the housing flange (19) facing away from the sheet metal profile part (22) is welded, so that the housing flange (19) between a screw head (33) of the screw bolt (25) and the sheet-metal profile part (10) is clamped, and in the event of a crash the traction battery (9) is displaced due to a crash until an inner wall of the housing flange duct (27) pushes the screw bolt (25) against an opening edge ( 51) of the sheet-metal part screw hole presses, specifically under shear stress on the screw bolt (25), characterized in that, in order to reduce the shear load, the weld nut (31) is extended with a shaft (35) which protrudes at least into the sheet-metal part screw hole, and that in the event of a crash, the screw bolt (25) presses against the opening edge (51) of the sheet-metal part screw hole with the welding nut shaft (35) in between. Body structure after Claim 1 , characterized in that the weld nut shaft (35) with a projection (a) projects beyond the side of the sheet metal profile part (22) facing the housing flange (19) or protrudes into the housing flange lead-through channel (27), and that in the event of a crash the Presses the inner wall of the housing flange feed-through channel (27) with the welding nut shaft (35) interposed against the screw bolt (25). Body structure after Claim 1 or 2nd , characterized in that the screw head (33) of the screw bolt (25) is braced against an opening edge region (37) of the housing flange through-channel (27), and / or that the weld nut shaft (35) with its, with the screw head (33 ) of the screw bolt (25) facing the end face (39) by an axial clearance (Δz) from the screw head (33) of the screw bolt (35). Body structure according to one of the preceding claims, characterized in that an inner wall of the housing flange through-channel (27) has a large-diameter channel section (43) and a small-diameter channel section (45) which merge into one another at an annular shoulder, and that the small-diameter channel section (45) on the Screw head (33) facing side opens into the opening edge area (37) of the housing flange lead-through channel (27) against which the screw head (33) of the screw bolt (25) is braced. Body structure after Claim 4 , characterized in that the axial length (b) of the small-diameter channel section (45) is smaller than the axial clearance (Δz) between the end face (39) of the weld nut shaft (35) and the screw head (33) of the screw bolt (25), and / or that the small-diameter channel section (45) and the axial clearance (Δz) are arranged in radial alignment with one another, and that in the event of a crash the large-diameter channel section (43) transversely to the screwing direction (S) in contact with the outer circumference of the weld nut shaft ( 35) comes and the small-diameter channel section (45) moves into the axial clearance (Δz). Body structure after Claim 5 , characterized in that the outer circumference of the weld nut shaft (35) merges with the circumferential outer corner (53) into the end face (39) of the shaft and that between the large-diameter channel section (43) and an annular surface (55) of the annular shoulder there is a circumferential one Inner corner (57) is stretched, which forms a negative shape of the outer shaft corner (53), and that in the event of a crash, the inner corner (57) in the housing flange lead-through channel (27) engages around the outer shaft corner (53) in a form-fitting manner. Body structure after Claim 5 or 6 , characterized in that the small-diameter channel section (45) projects radially inward beyond the large-diameter channel section (43) by a radial offset (Δr), and in that the radial offset (Δr) is smaller than a wall thickness of the shaft (35), so that in In the event of a crash, the small-diameter duct section (45) remains out of contact with the bolt shank (49) of the screw bolt (25). Body structure after Claim 5 or 6 , characterized in that the housing flange (19) is clamped against the sheet metal profile part (22) with the interposition of a clamping sleeve (59), and that the clamping sleeve (59) is supported on the housing flange (19) with a support base, and that the support base is one Vehicle lower sleeve section (61), which merges at a transition edge (63) in a radially outwardly projecting peripheral flange (65), and / or that the vehicle lower sleeve section (61) in contact with the large-diameter channel section (43) of the housing flange through-channel (27), while the transition edge (63) and the radially outwardly projecting support flange (65) is supported on the opening edge region (67) of the housing flange lead-through channel (27) facing the sheet metal profile part (22), and / or that the clamping sleeve (59) is supported with a sleeve section (60) on top of the vehicle at the opening edge region of the sheet-metal part screw hole.

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